Metallophthalocyanine coated porous silicon gas sensor selective to NO2

A composite device for sensing NO2 vapors was formulated by combining metallophthalocyanine (MPC) with porous silicon (PS). Thin films of MPC were coated onto the surface of PS and the surface resistivity was observed to change with the exposure to the vapors of NO2. Three different metals namely Co, Cd and Al were used to prepare the macromolecular complex. They provided different sensitivities for detection of NO2. The paper shows the superiority of the composite sensor in comparison to single film sensor.